Disk usage analyzers scan drives and show which folders and files hold the space, as treemaps, rings, charts or sorted lists.
This ranking weighs setup effort on your operating system, what a company pays once personal-use licences end, how results can be exported, and whether the tool comes from one named maker or a community project.
Vendors can pay for more visibility on this website, for example a higher place in a ranking or more room on a page. Commercial relationships can also affect which products we feature and how prominently. Every vendor link is marked the same, whatever the arrangement behind it. How that works.
In short
What disk usage analyzers software does
A disk usage analyzer scans a drive, share or server and ranks folders and files by size, so you can find what fills the disk and remove it.
The ranking follows five checks. Setup effort comes first, then real cost, then the route for getting data out, then lock-in, then the intended buyer. Vendors outside the best-known names fill places 1 to 3 when they exist, and the big brands rank from place 4. The reasoning behind the five tests, and behind having no score out of ten, is set out on the how we work page.
Fast Windows scanner reading the NTFS file table, plus a Mac edition
Ranked #1 of 12 in Best Disk Usage Analyzers in 2026.
Free tierPublished pricingElsewhere
Instead of walking every folder, WizTree takes NTFS metadata straight from the Master File Table, and counts hard-linked files once so shared data is not double counted. It shows a tree map, a tree view, a largest-files list and duplicate detection.
Results can go out as CSV or the clipboard, and the command line can dump the MFT. A Mac edition called WizTreeMac exists. Commercial use is the sticking point: it needs a Supporter Code, with distribution and enterprise licences on separate pages.
What stands out
NTFS table scan
Personal-use licence
Windows and macOS
Where it costs you
The page lists no prices or currency for Supporter Code, renewal or Enterprise licences, so a business cannot budget from it.
The company address and country are not given, which leaves a procurement team with a name only.
Right for
Windows users who want the quickest first scan and can license commercial use
Wrong for
Organisations wanting a published price before any purchase conversation
Not stated by the vendorFree for personal use; commercial use needs a Supporter Code, large organisations an Enterprise licence; amounts not shown on the page
Open-source Windows analyzer with treemaps, sunbursts and duplicate detection
Ranked #2 of 12 in Best Disk Usage Analyzers in 2026.
Free tierOpen sourcePublished pricingElsewhere
WinDirStat covers a wide set of views: treemaps, sunbursts, flame graphs, plus largest-files and file-type lists that compare logical with physical size. It can search by name, size, type or owner, find duplicates through content hashes with optional sparse hashing, and save and reopen scan snapshots.
CSV and JSON export, scan automation and file-system change monitoring are listed. It is for Microsoft Windows, and its source, wiki and issue tracker sit on GitHub.
What stands out
GPL v3 or later
Hash-based duplicates
Scan snapshots
Where it costs you
Faster scanning on local NTFS drives depends on running it elevated, so locked-down desktops may see slower results.
The page shows no imprint, owner or country, so there is no named company to hold a contract with.
Right for
Windows administrators who want an auditable, no-cost scanner with duplicate finding
Wrong for
Buyers who need a vendor with a support contract
Not stated by the vendorFree of charge under GPL v3 or later; no paid plans on the page
Mac disk visualiser sold as a one-time lifetime purchase
Ranked #3 of 12 in Best Disk Usage Analyzers in 2026.
Pricing on requestElsewhere
DaisyDisk calculates sizes while skipping clones and hard links, and can scan with administrator rights to reveal restricted files. It also scans Dropbox, Google Drive, OneDrive and Box remotely, keeps snapshots and previews files instantly.
One purchase covers five personal Macs at most, with minor updates and bug fixes included. For companies, corporate and portable IT licences and student discounts are available on request, and the privacy policy says no data is collected or transmitted.
What stands out
Mac only
Lifetime licence
Cloud storage scans
Where it costs you
The trial is offered without stating its length or limits, so evaluation terms must be asked about.
It runs on macOS 10.13 or newer only, so mixed Windows and Mac estates need a second tool.
Right for
Mac owners who prefer paying once and also need to scan cloud storage
Wrong for
Teams running Windows or Linux machines alongside their Macs
Not stated by the vendorOne-time purchase for a lifetime licence, no subscription; try-before-buying download; corporate and portable IT licences on request
JAM Software analyzer with a home edition and per-user paid editions
Ranked #4 of 12 in Best Disk Usage Analyzers in 2026.
Free tierSelf-hostablePublished pricingElsewhere
TreeSize is sold as Free, Personal and Professional editions. Personal adds duplicate file search and deduplication; Professional adds custom exports to PDF, Excel and HTML and command-line or task scheduler use.
NTFS and exFAT drives work, USB ones included, and the interface resembles Windows Explorer with pie, bar and treemap charts. Every edition operates entirely on a local basis. Pricing is per user per year with annual billing, and a perpetual licence is also listed without a price.
What stands out
Editions by user
On-premises only
PDF and Excel export
Where it costs you
The home edition is barred from Windows Servers, so any server work forces a paid tier.
Licences are tied to one user and one to three hard-assigned systems, and cannot be shared or used concurrently.
Right for
Windows teams needing exports, scheduling and a vendor-backed licence
Wrong for
Anyone who needs to scan servers without buying a licence
Not stated by the vendorFree edition for home use; Personal and Professional editions billed per user per year, with 14-day trials; perpetual licence offered
Portable treemap viewer with combinable filters and colour tags
Ranked #5 of 12 in Best Disk Usage Analyzers in 2026.
Free tierPublished pricingElsewhere
SpaceSniffer shows folder and file sizes as a treemap: a single click shows contents and a double click zooms in. Filters can combine file type, age, size and date in one expression, and four colour tags let you filter or exclude by tag.
An export module writes a textual report with a customisable layout. The latest release listed is 2.2.0.27. It is described as portable and freeware, with donations welcome, so the page offers no paid licence.
What stands out
Portable
Filter syntax
Colour tagging
Where it costs you
The page does not name the operating system, so compatibility must be tested before rollout.
The developer is named only through a site logo and link, with no country, which complicates a vendor review.
Right for
Technicians who want a portable treemap with strong age and size filters
Wrong for
Teams that need documented platform support or a licence
Not stated by the vendorFreeware with donations welcome; no price listed
Open-source Mac treemap tool with cheap Mac App Store copy
Ranked #6 of 12 in Best Disk Usage Analyzers in 2026.
Free tierOpen sourcePublished pricingElsewhere
GrandPerspective offers configurable views for files, packages and folders, with colour schemes, name search and advanced filters. It links to Finder to open or reveal items, uses Quick Look previews and lets you delete from the view.
Scan results can be saved and reloaded, and exported as an image or text. The built-in help is localised in 11 languages. The same app is on SourceForge at no cost and on the Mac App Store for a few dollars.
What stands out
GPL treemaps
Mac only
11 languages
Where it costs you
Current releases require macOS 14 or higher, so older Macs depend on older builds.
The page names a single author and no country, which limits the support options on offer.
Right for
Mac users wanting a no-cost treemap with filters and Finder links
Wrong for
Organisations needing vendor support or Windows coverage
Not stated by the vendorFree download from SourceForge; same app sold on the Mac App Store at a low fixed price
Text-mode analyzer for servers and any POSIX shell session
Ranked #7 of 12 in Best Disk Usage Analyzers in 2026.
Open sourcePricing on requestElsewhere
ncdu gives a browser-style text interface for directory trees, with optional colours and a configuration file. It runs on any POSIX-like system and ships as static Linux binaries, Zig and C source tarballs, and packages for many distributions plus Homebrew, MacPorts and Fink on macOS.
Scans can be written out with -o as JSON, or with -O in a binary form added in version 2.6. Parallel scanning arrived in 2.5 behind the -t8 flag.
What stands out
MIT licence
Terminal interface
JSON export
Where it costs you
Output is a text list with no graphical treemap, so non-technical staff will find it hard to read.
Parallel scanning with -t8 is not enabled by default, and the page does not mention importing exports.
Right for
Administrators inspecting remote Linux and Unix servers over a terminal
Wrong for
Staff who expect a graphical map of disk contents
Not stated by the vendorMIT-licensed and open source; the page shows no paid plans
Qt port of KDirStat for Linux, BSD and macOS desktops
Ranked #8 of 12 in Best Disk Usage Analyzers in 2026.
Pricing on requestElsewhere
QDirStat describes itself as directory statistics, KDirStat without any KDE. Stefan Hundhammer is named as the author, with copyright 2015 to 2025, and the licence in the repository is GPL-2.0.
The README covers Linux, BSD, Unix-like systems and macOS, and says that Windows users should look at Docker or WinDirStat. The steps are qmake6, make and sudo make install, after installing Qt 6, zlib and a C++ compiler.
What stands out
GPL-2.0
Qt 6 build
Linux and BSD
Where it costs you
The README lists no native Windows build, so mixed desktop fleets need another tool.
Installation means compiling from source, which is a barrier for non-developers.
Right for
Linux desktop users who want a KDirStat-style treemap without KDE
Wrong for
Windows users and anyone who cannot compile software
Not stated by the vendorNo charge; GPL-2.0 licensed source on GitHub, built from the repository
KDE radial map for local, remote and removable disks
Ranked #9 of 12 in Best Disk Usage Analyzers in 2026.
Pricing on requestElsewhere
Filelight is packaged for AppStream stores, Flathub, Snap, the Microsoft Store and nightly builds. It reads local, remote or removable disks, shows detailed file and folder information, offers configurable colour schemes and can delete oversized items directly.
It plugs into the Dolphin, Konqueror and Krusader file managers. The licence is GPL-2.0 or later, and the page names KDE as the maker.
What stands out
Radial map
KDE project
Linux and Windows
Where it costs you
No individual maintainer or company is named on the page, so accountability sits with the KDE community.
The Windows build comes from a store listing and nightly builds, which an IT team must vet separately.
Right for
KDE desktop users and mixed Linux and Windows machines needing a radial map
Wrong for
Teams needing a named vendor or written support terms
Not stated by the vendorNo charge, GPL-2.0 or later; installed through app stores and nightly builds
GNOME's own Disk Usage Analyzer for Linux desktop users
Ranked #10 of 12 in Best Disk Usage Analyzers in 2026.
Pricing on requestElsewhere
Baobab appears on the GNOME apps site as Disk Usage Analyzer, with Paolo Borelli, Stefano Facchini and Christopher Davis named as maintainers. Chosen folders, storage devices and online accounts can be scanned, with results in two layouts, tree and graphical.
It is installed from Flathub, is covered by GPL-2.0 or later, and accepts donations welcome for the GNOME Foundation. Distribution is via Flathub.
What stands out
GNOME app
Flathub install
Online accounts
Where it costs you
Only Linux is named, so Windows and Mac machines need a different tool.
The listed features stop at scanning and two views, with no export or duplicate search mentioned.
Right for
GNOME users wanting a simple scanner already close to the desktop
Wrong for
Anyone needing export, filtering or duplicate detection
Not stated by the vendorNo charge, GPL-2.0 or later; donations welcome for the GNOME Foundation
Flexense analyzer with server and enterprise editions and a command line
Ranked #11 of 12 in Best Disk Usage Analyzers in 2026.
Pricing on requestElsewhere
DiskSavvy is described as a disk space analyzer with a GUI and a command-line utility. Listed capabilities include analysis of network servers, file categorisation and filtering, pie charts, history timeline charts, built-in file classification, disk space usage reports and SQL database integration.
A separate DiskSavvy Server product and an Enterprise licence are linked from the home page, and the copyright runs from 2007 to 2026 under Flexense Ltd.
What stands out
GUI plus CLI
Server edition
History charts
Where it costs you
The home page shows no prices or currency, so cost is unknown until the licence pages are read.
No trial is mentioned and operating systems are not named, which makes testing on your platform uncertain.
Right for
Administrators wanting usage reports and history charts for network servers
Wrong for
Buyers who need visible prices and a trial first
Not stated by the vendorPurchase, Server and Enterprise licence pages linked; home page shows no prices and mentions no trial
Free Mac treemap tool whose listed download targets macOS 10.13 to 10.15
Ranked #12 of 12 in Best Disk Usage Analyzers in 2026.
Free tierPublished pricingElsewhere
Disk Inventory X shows file and folder sizes as treemaps, using a layout algorithm derived from KDirStat. The page credits Tjark Derlien, shows copyright 2019 and says the app is released under the GPL.
Its single download is version 1.3, for macOS releases 10.13 through 10.15, while the page also uses the name Mac OS X. There are no paid plans, and the only contact route is a link.
What stands out
GPL
KDirStat layout
Older macOS
Where it costs you
Version 1.3 targets older macOS releases only, so newer systems are not confirmed.
The page gives only a contact link, with no address, country or support terms.
Right for
Mac users on older macOS who want a simple no-cost treemap
Wrong for
Owners of current Macs wanting confirmed compatibility
Not stated by the vendorFree download under the GPL; no paid plans shown
A disk usage analyzer scans a drive, share or server and ranks folders and files by size, so you can find what fills the disk and remove it. The differences that matter are rarely in the feature list, so this is the order we would work through them.
01
Work out how much a sales call is worth to you
Prices are public at 6 products (WizTree, WinDirStat, TreeSize, SpaceSniffer, GrandPerspective, Disk Inventory X) and on request at the remaining 6, so budget time for quotes if your favourite is in that second group.
02
Weigh the vendor's home jurisdiction
The 12 companies behind this list are established in 1 countries, by region Elsewhere 12. Disclosure obligations attach to the company, so they travel with the vendor even when the servers stay at home.
03
Consider whether you want the source
Open source here means WinDirStat, GrandPerspective, ncdu. The price of self-hosting is the time your team spends maintaining it.
Disk usage analyzers on Windows: how WizTree, WinDirStat and TreeSize scan
Scan method decides how long you wait on a large drive. WizTree skips the folder walk by reading NTFS metadata, and WinDirStat scans faster on local NTFS drives only when run elevated. TreeSize handles NTFS and exFAT volumes and offers three chart types inside an interface modelled on Explorer.
SpaceSniffer is portable, but its page names no operating system,. Network shares matter too: WinDirStat lists shares and MTP devices, and WizTree can scan network drives. Run each candidate against your largest volume, with the same account you would use in production, and compare scan time, how hard links are counted and whether the result can be saved.
Time one scan of your largest volume per tool
Run the scan elevated and as a standard user
Check whether hard-linked files are counted once
Mac and Linux picks: DaisyDisk, GrandPerspective, QDirStat and Baobab
Platform support splits this market into separate camps. DaisyDisk and GrandPerspective are Mac tools, with GrandPerspective needing macOS 14 or higher, and Disk Inventory X offering a download for macOS 10.13 to 10.15. On Linux, QDirStat is built from source with Qt 6, Baobab installs from Flathub and is stated as Linux only, and Filelight adds a Windows build through the Microsoft Store.
DaisyDisk can scan four named cloud services, and Baobab lists online accounts. Match the tool to the oldest operating system you still support, because a tool that rejects a machine is useless on it. Then check how each is installed, since building from source is a real cost.
List the oldest macOS or Linux release you support
Check whether install is a package or a source build
Decide whether cloud storage needs scanning
Servers and terminals: ncdu and TreeSize on machines without a desktop
Servers rarely have a graphical session, which changes the shortlist. ncdu works in a terminal on POSIX-like systems and writes scans out as JSON, so you can scan on the server and read results elsewhere. TreeSize operates entirely on-premises, but the home edition excludes Windows Servers, so a paid edition is needed there.
DiskSavvy lists a server product and a command-line utility, though its home page shows no prices. Decide first whether you need a folder-level answer or a volume-level answer, because the two kinds of tool do not substitute for each other.
Confirm the tool runs without a desktop session
Test the export format on a real scan
Check licence terms for server operating systems
Licences and cost: personal use, one-time prices and open source in this category
Most tools here cost nothing, but the conditions differ. WizTree allows personal use at no charge, but business buyers need a Supporter Code, and large organisations an Enterprise licence. TreeSize bills Personal and Professional editions per user per year and ties each licence to one user and up to three assigned systems.
DaisyDisk sells a lifetime licence valid for five personal Macs at most, with corporate and portable IT options available if you ask. WinDirStat, ncdu and QDirStat are open source, so there is no seat to count, though also no vendor to call. Ask who is accountable when a scan misreports sizes, and keep a written licence for any tool used at work.
Check whether work use is covered by the free licence
Count users and machines against the licence wording
Name who supports the tool when something breaks
What goes wrong most often when buying disk usage analyzers software
Running a personal-use tool such as WizTree or TreeSize's home edition on company machines without reading the licence.
Choosing a scanner for one operating system and discovering the server fleet runs another, as with DaisyDisk or Baobab.
Deleting what a treemap highlights without checking whether the folder belongs to the system, a backup or a sync client.
Using df output to find large folders, when it only reports totals per mount point.
07
Frequently asked questions
8 answers
What is the best disk usage analyzers in 2026?
WizTree leads our ranking of 12. WizTree is published by Antibody Software Limited and reads the NTFS Master File Table directly, which is why a first scan feels quick.
It also scans non-NTFS and network drives and has command-line options. The catch is licensing: personal use is free, but a company must buy a Supporter Code, and the page shows no amounts, so check cost before rolling out.
Which disk usage analyzers tools publish their pricing?
The ones that do, with the model each states:
WizTree: Free for personal use; commercial use needs a Supporter Code, large organisations an Enterprise licence; amounts not shown on the page.
WinDirStat: Free of charge under GPL v3 or later; no paid plans on the page.
TreeSize: Free edition for home use; Personal and Professional editions billed per user per year, with 14-day trials; perpetual licence offered.
SpaceSniffer: Freeware with donations welcome; no price listed.
GrandPerspective: Free download from SourceForge; same app sold on the Mac App Store at a low fixed price.
Disk Inventory X: Free download under the GPL; no paid plans shown.
The other 6 quote per organisation.
Is there a free disk usage analyzers tool?
WizTree, WinDirStat, TreeSize, SpaceSniffer, GrandPerspective, Disk Inventory X offer a free tier or a free self-hosted edition.
Where are these disk usage analyzers vendors established?
Across 1 countries (Elsewhere 12):
WizTree: Not stated by the vendor.
WinDirStat: Not stated by the vendor.
DaisyDisk: Not stated by the vendor.
TreeSize: Not stated by the vendor.
SpaceSniffer: Not stated by the vendor.
GrandPerspective: Not stated by the vendor.
ncdu: Not stated by the vendor.
QDirStat: Not stated by the vendor.
Filelight: Not stated by the vendor.
Baobab: Not stated by the vendor.
DiskSavvy: Not stated by the vendor.
Disk Inventory X: Not stated by the vendor.
Which disk usage analyzers tools are open source?
WinDirStat, GrandPerspective, ncdu.
Which disk usage analyzers tools can you host yourself?
TreeSize. The remaining 11 run only on the vendor's servers.
What should you use instead of WizTree?
WinDirStat and DaisyDisk are the next two on this page. WinDirStat is for Windows administrators who want an auditable, no-cost scanner with duplicate finding; DaisyDisk is for Mac owners who prefer paying once and also need to scan cloud storage.
Who should not buy WizTree?
Organisations wanting a published price before any purchase conversation. The page lists no prices or currency for Supporter Code, renewal or Enterprise licences, so a business cannot budget from it..
This list covers 12 disk usage analyzers products. A product we left out can be put to us by its maker, with a short note on its purpose and its customers; we decide on inclusion ourselves. The rules are under software advice.
